Warrant Officer Dan was a chopper pilot who appears in the Season 4 episode of M*A*S*H titled Dear Mildred. The part of Stratton is played by Buck Young who also played the part of another helicopter pilot O'brien in Dr. Pierce and Mr. Hyde (Season 2) and an unnamed M.P. in Dear Dad (Season 1).
About Dan[]
Dan's last name is not given in the credits nor in the episode dialogue. He arrives at the 4077th to deliver some mail. While there he asks Hawkeye, B.J. and Radar if there was a sharpshooter available. He had spotted an injured horse and wanted to put it out of its misery. Radar, however, refuses to has the horse shot. He persuades the doctors to go with him to rescue it and treat it. Dan agrees to help them look for the horse. Hawkeye, B.J. and Radar go off in a truck which Dan directs them from his helicopter. The horse is located and subsequently given to Colonel Potter as a gift for his wedding anniversary.
Another view of Dan. The Warrant Officer insignia on his cap is clearly shown.